Measurement of corner separation zone response on a compression ramp to plasma actuation within the hypersonic boundary layer

Brock E Hedlund, Alec W Houpt, Stanislav V Gordeyev, Sergey B Leonov
2017 IOP Conference Series: Materials Science and Engineering  
This study was performed to characterize the dominant frequencies present in the boundary layer uptsream of and in the corner separation zone of a compression surface in Mach 4.5 flow and to determine a control effect of transient plasma actuation on the boundary layer. Schlieren imaging was used to distinguish the corner separation zone for 20°, 25°, and 30° compression ramps mounted on flat plates. Spectra of the natural disturbances present in the boundary layer and separation zone were
more » ... red using a high-speed Shack-Hartmann wavefront sensor and surface mounted PCB pressure sensors while varying flow parameters by adjusting total pressure, temperature, and ramp angle. Shallow cavity discharge plasma actuators were used as a high-frequency localized thermal forcing mechanism of the boundary layer. The plasma effect was negligible for forcing frequencies (50 kHz) below the natural dominant frequency (~55-80 kHz). High frequency perturbations that can promote the transition to turbulence were amplified when the plasma forcing frequency (100 kHz) was higher than the natural dominant frequency (~55-80 kHz). This technique can potentially be used for active control of hypersonic boundary layer transition and the supersonic flow structure on the compression surface.
doi:10.1088/1757-899x/249/1/012013 fatcat:hctpd6uqgfgibfzt3acmytb64q